Everyone's noted Yahoo's CEO churn. But Yahoo has also had a ton of turnover lower down in the executive ranks.

Ash Munshi, who parted ways with the company over the summer, is, by our count, the fifth senior leader in charge of Yahoo's technology or products to leave in the last two and a half years. He followed Ash Patel, Ari Balogh, Blake Irving, and Raymie Stata out the door.

(Pop quiz: Can you name any products they pushed out the door that contributed to Yahoo's bottom line?)

Yahoo CEO Marissa Mayer should not replace Munshi, whose position hasn't been filled in the intervening months.

Her previous employer, Google, does not have a chief technology officer. That's because technology is everyone's job at Google. That's how it should be at Yahoo.

If Yahoo were still defining itself as a media company, it might make sense to have a chief technology officer—a senior advisor to the CEO who explains this mystifying tech stuff and knows how to speak to engineers.

But Mayer, a computer scientist by training, is redefining Yahoo as a products company—one where technology infuses everything and isn't a separable discipline.

If anyone is in charge of Yahoo's technology now, it's Mayer. And that's how it should be.